2 * Copyright (C)2003,2004 USAGI/WIDE Project
4 * Header for use in defining a given L3 protocol for connection tracking.
7 * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
9 * Derived from include/netfilter_ipv4/ip_conntrack_protocol.h
12 #ifndef _NF_CONNTRACK_L3PROTO_H
13 #define _NF_CONNTRACK_L3PROTO_H
14 #include <linux/netlink.h>
15 #include <net/netlink.h>
16 #include <linux/seq_file.h>
17 #include <net/netfilter/nf_conntrack.h>
19 struct nf_conntrack_l3proto
21 /* L3 Protocol Family number. ex) PF_INET */
28 * Try to fill in the third arg: nhoff is offset of l3 proto
29 * hdr. Return true if possible.
31 int (*pkt_to_tuple)(const struct sk_buff *skb, unsigned int nhoff,
32 struct nf_conntrack_tuple *tuple);
35 * Invert the per-proto part of the tuple: ie. turn xmit into reply.
36 * Some packets can't be inverted: return 0 in that case.
38 int (*invert_tuple)(struct nf_conntrack_tuple *inverse,
39 const struct nf_conntrack_tuple *orig);
41 /* Print out the per-protocol part of the tuple. */
42 int (*print_tuple)(struct seq_file *s,
43 const struct nf_conntrack_tuple *);
45 /* Print out the private part of the conntrack. */
46 int (*print_conntrack)(struct seq_file *s, const struct nf_conn *);
48 /* Returns verdict for packet, or -1 for invalid. */
49 int (*packet)(struct nf_conn *conntrack,
50 const struct sk_buff *skb,
51 enum ip_conntrack_info ctinfo);
54 * Called when a new connection for this protocol found;
55 * returns TRUE if it's OK. If so, packet() called next.
57 int (*new)(struct nf_conn *conntrack, const struct sk_buff *skb);
60 * Called before tracking.
61 * *dataoff: offset of protocol header (TCP, UDP,...) in skb
62 * *protonum: protocol number
64 int (*get_l4proto)(const struct sk_buff *skb, unsigned int nhoff,
65 unsigned int *dataoff, u_int8_t *protonum);
67 int (*tuple_to_nlattr)(struct sk_buff *skb,
68 const struct nf_conntrack_tuple *t);
70 int (*nlattr_to_tuple)(struct nlattr *tb[],
71 struct nf_conntrack_tuple *t);
72 const struct nla_policy *nla_policy;
75 struct ctl_table_header *ctl_table_header;
76 struct ctl_table *ctl_table_path;
77 struct ctl_table *ctl_table;
78 #endif /* CONFIG_SYSCTL */
80 /* Module (if any) which this is connected to. */
84 extern struct nf_conntrack_l3proto *nf_ct_l3protos[AF_MAX];
86 /* Protocol registration. */
87 extern int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto);
88 extern void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto);
89 extern struct nf_conntrack_l3proto *nf_ct_l3proto_find_get(u_int16_t l3proto);
90 extern void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p);
92 /* Existing built-in protocols */
93 extern struct nf_conntrack_l3proto nf_conntrack_l3proto_generic;
95 static inline struct nf_conntrack_l3proto *
96 __nf_ct_l3proto_find(u_int16_t l3proto)
98 if (unlikely(l3proto >= AF_MAX))
99 return &nf_conntrack_l3proto_generic;
100 return rcu_dereference(nf_ct_l3protos[l3proto]);
103 #endif /*_NF_CONNTRACK_L3PROTO_H*/